Fuel rack position sensor function - GF07.04-P-5022-01H

Engine 605, 606

Fig 1: Identifying Fuel Rack Position Sensor Function

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function

Start

Turning the ignition to "ON" causes the IFI [ERE] fuel quantity actuator (Y23/1) to move the control rod (depending on the coolant temperature) into the start position (max. 19.5 mm), direction "A".

Fig 2: Identifying Measuring Coil

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

The IFI [ERE] control module (N3/7) energizes the reference coil (b) with a frequency of 10 kHz and a pulsating direct current (approx. 1.5V). The short-circuit ring (e) of the control rod (2t) moves away from the measuring coil (d). This maximizes the magnetic field (inductance) of the measuring coil (d) (2.8V). The measuring coil (d) therefore displays the smallest drop in voltage.

Idling, abrupt acceleration

Amplitude modulation

Fig 3: Identifying Measuring Coil

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Fig 4: Identifying Fuel Rack Position Sensor Function - Idling, Abrupt Acceleration

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Engine braking

During engine braking (zero delivery, 0 mm control rod travel) the short-circuit ring (e) of the control rod (2t) moves in direction "B" towards the measuring coil (d). This reduces the magnetic field (1.6 V). The measuring coil (d) therefore displays the largest drop in voltage

Drive mode

In drive mode, the short-circuit ring (e) of the control rod moves between the minimum and maximum ranges depending on the position of the accelerator pedal.

The frequency of 10 kHz remains unchanged under all operating conditions.

Control rod travel after 30 s, ignition "ON"

Fig 5: Measuring Coil And Reference Coil

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.